Series street-lighting socket



y 1929. H. E. BUTLER- SERIES STREET LIGHTING SOCKET FiledDec. 11, 1925Fig.2.

\nvenb or Henry E. Butler by )r M His A'bb orne'y Patented May 14, 1929.

* UNITED STATES 1,713,215 PATENT OFFICE.

HENRY E. BUTLER, OF SGOTIA, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COM-PANY, A CORPORATION OF NEW YORK.

SERIES STREET-LIGHTING SOCKET.

Application filed December The present invention relates to seriesstreet-lighting sockets, and especially to sockets of the type whichcomprise a film cut-out.

he object of my invention is to provide an improved arrangement wherebythere is provided .in connection with series streetlighting sockets, asupply of film cutouts so that when a film cut-out is punctured, due tothe burning of a la .11), a supply of film cutouts will be present for,renewal purposes.

F or a consideration of what I believe to be novel and my invention,attention is directed to the accompanying description .and the claims.-appended thereto.

In the drawing, Fig. 1' is a sectional View of series street-lightingsocket embodying my invention, and Fig. 2 is detail perspective viewthereof.

Referring to the drawing, indicates a receptacle having a. base 11 and abracket 12 provided with a threaded end 13 adapted to be connected to alamp post bracket... Carried by base 11 are two opposed spring contacts14 and 15 to which are connected binding posts 16 and 17 which receivethe series line terminals. 18 indicates a lamp socket having a threadedshell 19 adapted to receive the threaded end 20 of an incandescent lamp21. Shell 19 forms one terminal connection for the lamp, the other beingformed by a central contact 22. Contact 22 and shell 19 are connected byscrews 23 and 24 to terminal spring contacts 25 and 26 which are adaptedto be inserted between spring contacts 14 and 15 to form the circuitconnections for connecting the lamp into the series circuit. and also toform a supporting means for the lamp socket. Spring contacts 25 and 26have parallel outer ends as is indicated at 27 and 28, below which arebowed-out portions 29 and 30. Below bowed-out portions 29 and 30 thecontacts have long, straight, substantially parallel portions 31 and 32.33 is an insulating plate which surrounds contacts 25 and 26 at theirlower ends. Located between ends 27 and 28 is a film cut-out 34 ofsuitable construction. As is well known. it may comprise a small diskembodying an insulating film of a nature such that when the voltageimpressed upon it exceeds a predetermined amount, it will break down,connecting together terminals 27 and 28.

The foregoing arrangement may be taken as typical of any suitable seriescircuit arran ement embodying a film cut-out. The

11, 1925. Serial No. 74,830.

specific arrangement shown is a known one and one in extensive use atthe present time. It operates as follows \Vith a film cut-out 3i betweencontact ends 27 and 28 and a lamp in the socket, current enters by wayof binding post 16, flows through spring contacts 14 and 25 and socket23 to central contact 22; thence through the lamp filament to shell 19and by way of socket 24 and spring contacts 26 and 15 to terminals 17.As long as the lamp is in circuit the po tential across spring contactends 27 and 28 is not suiiicieut to rupture the film 3 1 and hence theends remain insulated from each other. In case the lamp burns out or isremoved, the series circuit is interrupted. This builds up a potentialacross Contact ends 27 and 28 sufiiciently high to rupture the film andeifect a connection between such ends. A circuit is thereby closedaround the burnedout lamp as is obvious and the operation of theremaining lamps in the series circuit is not interfered with. Inordinary streetlighting practice, lamps are used until they burn out,which means, of course, that the insulating films are ruptured. Theattendant. when he finds a lamp burned out, must, therefore, not onlyput in a new one but renew the film also. IVhen films of the disk type,such as the film 34 shown in the drawing, are used, it is customary forthe attendant to carry a supply of these films in his pocket. Inrenewing a lamp, the lamp receptacle is removed, the punctured film 34pulled from between contact ends 27 and 28 and a new one put in itsplace. These disk films are comparatively delicate in structure and mustbe handled carefully and kept clean if they are to perform theirintended function. In carrying the disk films in the pocket, they oftenbecome dirty and also at times they become soiled from the attendantshands. This means that they do not then perform their function as theyshould. Also, it happens sometimes that an attendant will not have filmswith him when fixing a lamp and in this case, he may insert some otherkind of insulating material between the contact ends, a thing which is,of course, objectionable.

According to my present invention, I proride in connection with thecontact terminals 31 and 32 a suitable receptacle 35 which is in theform of a box and which may be formed of any suitable material.Preferably, a waterproof material is used. Receptacle 35 is of thebottom of the receptacle.

a size to hold a number of disk films 3a or other suitable devicesintended for use between contact ends 27 and 28. In the present instancereceptacle comprises two members which telescope one within the other,this formed of metal, for example, and may be provided with a bowed-outportion 37 which forms a part which engages the spring-contact. Thedistance between the parallel portions of the spring contacts in seriesreceptacles varies somewhat and the width of receptacle 35 plus spring36' is such that the receptacle will be held firmly in position in thecase of the most widely separated spring 1 contacts, and such thatspring 36 will give sut-.

ficiently to permit or the receptacle being in serted between the mostclosely spaced spring terminals. In this connection, it will beunderstood that this variation in spacing is due to commercialmanufactureand at the most is not very much. As a result, the springmember 36 readily takes care of the variations met with.

lVith the above described arrangement, a number of the film members3t'are placed in the receptacle 35 and the receptacle is then slidbetween the parallel portions 31 and 32 of the contact terminals 25 and26, the dimensions of the receptacle being such, preferably, that itlies entirely within the confines of such parallel portions. lVith thisarrangement, therefore, there is present at the series socket a supplyof the film cut-outs and as a result the attendant need. not carry themin his pocket. When renewing the lamp, it is necessary only to slide thereceptacle 35 from between the parallel portions 31 and 32, remove afilm cut-out theretrom and again replace the receptacle. The attendantmay carry along V I hand this 10th day of December, 1925, a

with him a package. of the receptacles 35 with film cut-outs therein andin case in renewing a lamp, he finds all the film cut-outs remove theempty receptacle 35 and substitute a full one for it. By this means, itwill be seen that the film cut-outs carried by the atin one of thereceptacles empty, then he can ten'dant are always protectedby therecep':

it between the spring contacts below their outer ends.

2. The combination with a series street lighting socket comprisingspring contacts between the ends of which a film cut-out is held, saidcontacts having spaced, parallel portions, of a receptacle adapted tohold a plurality of extra film cut-outs, said receptacle being of asizeto fit between said parallel portions and being at least in partyieldable to adapt it to variations in distances between I said parallelportions;

3. The combination with a series streetlighting socket comprising springcontacts between the ends of which a film cut-out 15 held, said contactshaving spaced parallel portions, of a receptacle adapted to hold a Iplurality of extra film cut-outs, said receptacle being of a size to fitbetween said parextra film cut-outs, said're'ceptacle being of a size tofit between said parallel portions, and

V a yielding spring member attached to a wall ot the receptacle andadapted to'engage one of said parallel'portions to hold'the rec'eptaclein position between said parallel per tions. 7 y A In witness whereof Ihave hereunto set my HENRY BUTLER.

